Slip proof device in combination with a bit for a hand drill chuck

ABSTRACT

A slip proof device for a chuck includes a recessed area adapted to receive therein a collar, a through hole defined through a bottom face defining the recessed area to allow a bit to extend therethrough, and a first threaded hole defined in a periphery of a side wall defining the recessed area so as to adapt to correspond to one of three cavities in the collar and to allow a first abutting element to extend through the first threaded hole and one of the cavities to secure the slip proof device relative to the chuck. The bit includes a free end adapted to be clamped by the three claws of the chuck and a truncated surface longitudinally defined on the bit such that a second abutting element is able to abut the truncated surface to secure the bit relative to the slip proof device.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a slip proof device incombination with a bit for a hand drill chuck, and more particularly toa slip proof device adapted to a chuck so as to obviate slip between thechuck and the bit.

[0003] 2. Description of Related Art

[0004] A conventional hand drill is equipped with numerous bits fordifferent requirements. Before using the hand drill, the operatornormally will mount a proper bit on a chuck of the hand drill by using achuck key. In order to have better understanding of how the conventionalhand drill works, refer to FIG. 5, wherein the hand drill has a chuck(40) ready to clamp a bit (50). The chuck (40) has a collar (41) with athrough hole (42) radially extending through the collar (41) and threeclaws (43) movably received in the collar (41) to clamp the bit (50).When the conventional hand drill is in use, the operator uses the chuckkey (not shown) to separate the claws (43), after which, a proper bit(50) is inserted into the space defined by the claws (43). Then anabutting element (52) threadingly extends into the through hole (42) toabut a truncated surface (51) such that the bit (50) is secured amongthe claws (43). Although this type of hand drill has been usedsuccessfully for years, drawbacks still impede the operator, which are:

[0005] {circle over (1)} Engagement between the claws (43) and the bit(50) is not secured even with the assistance of the abutting element(52) so that the bit may not be driven to rotate by the turning chuckduring operation, or the bit may even separate from the hand drill.

[0006] {circle over (2)} When the diameter of the bit is small, thedistance among each of the claws is too small to have an effectiveclamping force to hold the bit.

[0007] {circle over (3)} If the diameter is small, the abutting elementshould be small so as to properly abut a side face of the bit, whichresults in that the abutting force of the abutting element is noteffective.

[0008] To overcome the shortcomings, the present invention tends toprovide an improved slip proof device in combination with a bit tomitigate and obviate the aforementioned problems.

SUMMARY OF THE INVENTION

[0009] The primary objective of the present invention is to provide animproved slip proof device adapted to engage with the chuck of the handdrill so as that the requirement of the abutting element is eliminated.

[0010] Another objective of the present invention is to provide animproved bit incorporated with the slip proof device such that the bitis able to be securely clamped by the hand drill.

[0011] Other objects, advantages and novel features of the inventionwill become more apparent from the following detailed description whentaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a perspective view of the slip proof device incombination with a bit of the present invention;

[0013]FIG. 2 is an exploded perspective view of the slip proof deviceand the bit in FIG. 1;

[0014]FIG. 3 is a schematic side plan view showing the engagement of theslip proof device with the bit;

[0015]FIG. 4 is a schematic view showing the bit incorporation with theslip proof device of the present invention; and

[0016]FIG. 5 is a cross sectional view showing the relationship betweenthe bit and the claws of the conventional hand drill.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0017] With reference to FIGS. 1 and 2, a chuck (30) which issubstantially the same as the conventional one has a first collar (31)and a second collar (32) received in the first collar (31). The secondcollar (32) has three cavities (33) equally defined in a periphery ofthe second collar (32) and three claws (34) movably received in thesecond collar (32).

[0018] A slip proof device (10) in accordance with the present inventionis adapted to engage with the chuck (30). The slip proof device (10) isU-shaped in cross section and has a recessed area (11), a through hole(12) defined in a bottom face defining the recessed area (11), a firstthreaded hole (14) defined in a side face of the recessed area (11) tocorrespond to a first bolt (141), two cutouts (15) peripherally definedin the side face of the recessed area (11) and a second threaded hole(16) defined in the side face of the recessed area (11) to correspond toa second bolt (161). It is noted that the first threaded hole (14) isaligned with one of the cavities (33) of the chuck (30) and the twocutouts (15) are defined to align with the remaining two cavities (33)of the chuck (30).

[0019] A bit (20) in accordance with the present invention has a freeend (21) adapted to correspond to the three claws (34) of the chuck (30)and a truncated surface (22) longitudinally defined along the bit (20).

[0020] With reference to FIGS. 3 and 4, when the slip proof device (10)and the bit (50) are to be incorporated with the chuck (30), the freeend (21) of the bit (20) is first inserted through the through hole (12)and into a space defined by the three claws (34) of the chuck (30). Thenthe operator uses the chuck key (not shown) to tighten the three claws(34) to secure the bit (20) in the chuck (30). Thereafter, the slipproof device (10) is adapted to engage with the second collar (32) ofthe chuck (30) with the first threaded hole (14) aligned with one of thecavities (33) in the second collar (32) and the two cutouts (15) alignedwith the remaining two cavities (33) of the chuck (30). Then the secondabutting element (26) threadingly extends into the second threaded hole(16) to abut the truncated surface (22) of the bit (20) such that thebit (20) is firmly clamped in the slip proof device (10). After the bit(20) is secured in the chuck (30) and the slip proof device (10), thefirst abutting element (141) threadingly extends through the firstthreaded hole (14) and into the aligned cavity (33) of the second collar(32).

[0021] With such an arrangement, it is noted that when the slip proofdevice (10) incorporated with the bit (20) is adapted to engage with thechuck (30), the problem raised by the too-small diameter of the bit isobviated. Furthermore, because the bit (20) has the truncated surface(22) which is firmly abutted by a free end of the second abuttingelement (161), the operator need not worry that the bit (20) may slipduring operation.

[0022] It is to be understood, however, that even though numerouscharacteristics and advantages of the present invention have been setforth in the foregoing description, together with details of thestructure and function of the invention, the disclosure is illustrativeonly, and changes may be made in detail, especially in matters of shape,size, and arrangement of parts within the principles of the invention tothe full extent indicated by the broad general meaning of the terms inwhich the appended claims are expressed.

What is claimed is:
 1. A slip proof device in combination with a bit fora chuck having a collar with three claws movably received in the collarand three cavities equally defined in a periphery of the collar, theslip proof device comprising: a recessed area adapted to receive thereinthe collar; a through hole defined through a bottom face defining therecessed area to allow the bit to extend therethrough; and a firstthreaded hole defined in a periphery of a side wall defining therecessed area so as to adapt to correspond to one of the three cavitiesin the collar and to allow a first abutting element to extend throughthe first threaded hole and one of the cavities to secure the slip proofdevice relative to the chuck; and the bit comprising a free end adaptedto be clamped by the three claws of the chuck and a truncated surfacelongitudinally defined on the bit such that a second abutting element isable to abut the truncated surface to secure the bit relative to theslip proof device.
 2. The slip proof device in combination with a bit asclaimed in claim 1, wherein the slip proof device further has a secondthreaded hole defined in the periphery of the side wall to allow thesecond abutting element to extend through the second threaded hole toabut the truncated surface of the bit so as to secure the bit.
 3. Theslip proof device in combination with a bit as claimed in claim 1,wherein the slip proof device further has two cutouts defined in theside face defining the recessed area to adapt to correspond to remainingtwo cavities of the chuck.
 4. The slip proof device in combination witha bit as claimed in claim 2, wherein the slip proof device further hastwo cutouts defined in the side face defining the recessed area to adaptto correspond to remaining two cavities of the chuck.